Maugham explains how he conceived the story from a passage of Dante’s Purgatorio that he read during his study of Italian in Florence. The story is of Pia, a noble lady of Siena, whose husband took her to his castle at Maremma on suspicion of adultery, thinking that she would die from the noxious vapors. However, as the lady’s death was taking a long time, her husband grew impatient and threw her out of the window. The story stayed with Maugham, and he imagined that such events could happen in Hong Kong. However, in order to protect members of the British Empire living there, he changed the location to the fictional Tching-Yen. This has since been changed back to Hong Kong.

Kitty and her lover, Charles Townsend, are in her bedroom when they sense the doorknob turning and a presence in the house. Kitty imagines that her husband, Walter, has discovered them and is terrified. Townsend attempts to dismiss her fears.

Kitty and Townsend speculate about what Walter would do if he found out about their affair. Townsend suspects that Walter might be too shy and reserved to do anything. He reinforces that they should not worry about their “mysterious visitor” (9).